Is there a list somewhere of the areas of the hard drive that aren't backed up by Time Machine? And does reinstalling from Time Machine install everything from the backup or just parts of it?

I like to tweak things a lot, like customizing the system Apache server and installing stuff into /usr/local (Max Howell's Homebrew, for instance), so I'd like to double check what areas I might lose if I needed to reinstall from a Time Machine backup (whole disk image backups seem a bit overboard for my tastes).